On Thu, Aug 27, 2020 at 4:10 AM Ed Greshko <ed.greshko@xxxxxxxxxxx> wrote: > > On 2020-08-27 09:38, Chris Murphy wrote: > > [egreshko@localhost ~]$ zramctl > NAME ALGORITHM DISKSIZE DATA COMPR TOTAL STREAMS MOUNTPOINT > /dev/zram0 lzo-rle 1.2G 510.6M 159.7M 167.6M 1 [SWAP] > > Effective compression ratio is 3:1. Also, that's at the low end of > what I regularly see. High end 4:1. > > > I don't know how to interpret the above to come up with a compression ration. DATA/COMPR is the actual compression ratio DATA/TOTAL is the effective compression ratio, which includes a bit of overhead and fragmentation of the zram device (the difference between COMPR and TOTAL) > [egreshko@f33g ~]$ uptime ; zramctl > 17:50:18 up 0 min, 1 user, load average: 1.89, 0.55, 0.19 > NAME ALGORITHM DISKSIZE DATA COMPR TOTAL STREAMS MOUNTPOINT > /dev/zram0 lzo-rle 1.2G 4K 74B 12K 1 [SWAP] > > A bit later on I login from the console and start a gnome-terminal session > > [egreshko@f33g ~]$ uptime ; zramctl > 17:56:13 up 6 min, 2 users, load average: 0.63, 0.45, 0.23 > NAME ALGORITHM DISKSIZE DATA COMPR TOTAL STREAMS MOUNTPOINT > /dev/zram0 lzo-rle 1.2G 137M 42.9M 46M 1 [SWAP] > > And after doing sudo dnf --refresh check-update later on, I now see > > [egreshko@f33g ~]$ uptime ; zramctl > 18:09:41 up 20 min, 2 users, load average: 0.07, 0.04, 0.09 > NAME ALGORITHM DISKSIZE DATA COMPR TOTAL STREAMS MOUNTPOINT > /dev/zram0 lzo-rle 1.2G 184.9M 61.4M 64.7M 1 [SWAP] > I suspect zram-fraction=0.75 also would have succeeded. But it's fine to leave it set to 1.0. And as these are VMs mainly for testing, you could even set it to 2.0, and see if you run into issues. The other reason for caps for systems with more memory, is the zram device does have a bit of overhead. It's cheap and worth it if the zram device is being utilized. But it's a waste, however small, if the zram device isn't being used. In your case, it'd be used so you could test with a fraction anywhere between 0.5 and 2.0. If you don't want to test it, 1.0 is pretty safe. -- Chris Murphy _______________________________________________ test mailing list -- test@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe send an email to test-leave@xxxxxxxxxxxxxxxxxxxxxxx Fedora Code of Conduct: https://docs.fedoraproject.org/en-US/project/code-of-conduct/ List Guidelines: https://fedoraproject.org/wiki/Mailing_list_guidelines List Archives: https://lists.fedoraproject.org/archives/list/test@xxxxxxxxxxxxxxxxxxxxxxx
